Many people along the East Coast are evacuating their homes ahead of Hurricane Florence. The storm is expected to make landfall in North and South Carolina later this week. Leaders of those states as well as Virginia, Maryland and Washington, D.C., have declared states of emergency. They're warning about storm surges, heavy winds, floods and power outages.

We start our coverage this hour with NPR's Sarah McCammon, who is in Virginia Beach. Hi, Sarah.

SARAH MCCAMMON, BYLINE: Hi, Ari.

SHAPIRO: How are things where you are?

MCCAMMON: Well, it's been almost eerily sunny most of today, but a storm is coming. Some people are staying to ride it out. And more than a million people across the region have been told to evacuate. Earlier today, I talked to Ariana Montemayor. She's a freshman at Old Dominion University in Norfolk, Va., and her school is in the evacuation zone. We spoke when she was getting ready to go to the airport and fly to Texas to be with family.

ARIANA MONTEMAYOR: You know, when they say that freshman year is going to be, you know, different and it will be exciting, this is not what exactly I had in mind - you know? - having to leave because of a hurricane. Only been in college for about, like, two weeks. So it was good while it lasted. We'll see when I'm back - hopefully Sunday (laughter).

MCCAMMON: Her university is just one of many colleges and schools that have canceled classes. And she says she's worried about her new friends, some of whom live in the area and are staying behind.

SHAPIRO: Well, tell us about those people who've chosen to stay behind even though they might be in the path of the storm.

MCCAMMON: Yeah. Well, the people who've been told they have to leave, those under mandatory evacuation, tend to live near the water, as you might expect. For those who are staying in their homes or with friends on higher ground, they've been busy getting ready. And that's leading to some shortages of supplies. Here in Virginia Beach, stores are selling out of water. I've been to several in the last few days that are out of those big water jugs. And so people are buying smaller bottles and seltzer and sports drinks. I'm also seeing lines for gasoline. And it's getting harder to come by cash. One ATM in my neighborhood was only dispensing a grand total of $20 at a time this afternoon.

SHAPIRO: Can you tell us more about how officials are making the call whether to force people to evacuate or allow them to stay where they are?

MCCAMMON: That can be a really tough decision, whether or not to order an evacuation. You know, the path and intensity of this hurricane can shift from hour to hour as you look at projections. If you don't make the call soon enough, the results of course can be catastrophic. And there are also risks to evacuating too soon. You can have too many people moving too quickly at the same time. That can overwhelm the roads. And with a storm this big, it's kind of hard to know where to tell people to go.

I talked to Ray Toal. He's the former director of coastal resilience research at Old Dominion. And he pointed out that heavy rain is expected in inland areas, too.

RAY TOAL: You know, if you go west, you're basically following the track of the storm because it's actually going to be - I think the rains and the flooding is going to be worse west of I-95. So where do I go?

MCCAMMON: And in North Carolina, Governor Roy Cooper made the unusual decision to evacuate barrier islands along the coast. Here was his advice to residents of those areas.

(SOUNDBITE OF PRESS CONFERENCE)

ROY COOPER: The waves and the wind this storm may bring is nothing like you've ever seen. Even if you've ridden out storms before, this one is different. Don't bet your life on riding out a monster.

SHAPIRO: Sarah, how are people who live further inland weighing this decision, where it may not be as clear-cut whether to stay or go?

MCCAMMON: Right. There are a lot of factors for people to think about - medical needs, family concerns, pets, house stormproof they think their home is. You know, I've talked to friends and neighbors here in the Virginia Beach area, and they're all making different decisions. And I have been juggling reporting on this storm with helping my spouse sort of board up our house as much as we can and take our kids to a safer place. Some people, quite frankly, have nowhere to go. Hotels are getting booked up. Not everyone can afford hotels. And with so many people living in these areas that could be affected, there are just only so many places people can flee from the storm.